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Littelfuse Electronics Circuit Protection Product Selection Guide

Littelfuse Electronics Circuit Protection Product Selection Guide
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Littelfuse Electronics Circuit Protection Product Selection Guide - 1

Expertise Applied | Answers Delivered Electronics Circuit Protection Product Selection Guide A guide to selecting Littelfuse circuit protection components for electronic applications.

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Littelfuse Electronics Circuit Protection Product Selection Guide - 2

Broadest and Deepest Portfolio of Product Backed by Unparalleled Circuit Protection Expertise About this guide This guide provides a summary of key circuit protection consideration factors, descriptions of the technologies Littelfuse offers, and product selection tables. It is designed to help you quickly find a protection solution appropriate to your application. Topic Littelfuse Circuit Protection Technologies Overcurrent Protection Technologies Fuses Positive Temperature Coefficient Devices (PTCs) Overvoltage Suppression Protection Varistors (MOVs, MLVs) Gas Discharge Tubes (GDTs) TVS...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 3

WHY CHOOSE CIRCUIT PROTECTION Circuit protection devices interrupt overcurrent events and divert overvoltage transients. They increase safety and enable end products to survive harsh electrical conditions. Most electrical and electronic equipment require circuit protection devices. In many cases they must be installed to comply with safety and performance standards before the end products can be sold or used. Beyond this, strategically-selected protection devices will: • Improve end-product uptime, sustainability and reliability • Assure low warranty return, repair and replacement costs •...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 4

Littelfuse Circuit Protection Technologies Technology Key Features and Protection Characteristics When / Where Typically Used Surge Energy Rating Range Typical Voltage Clamping Speeds Typical Capacitance/ Insertion Loss Mounting/ Size/Packaging Options Overcurrent Protection Technologies: Fuses Completely stop current flow, which helps to identify faults; Wide range of options Ultimate protection for sensitive/ expensive/critical components Low thru Very High Series impedance measured in nH Very Extensive Range of Options Resettable; No device replacement after most common overcurrent...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 5

1. Fuses and Holders — Fuses– Full range including surface mount, axial, glass or ceramic, thin-film or Nano2® style, fast-acting or Slo-Blo® fuse. Clips– Used in applications that require a fuse to be easily mounted to a PCB, but real-estate is scarce. Clips are also ideal for high-current applications, allowing for better heat management of the fuse. They are the most economical solution. Blocks– An alternative solution to Clips but with easier placement on the PC board during manufacturing. In some instances, Blocks may provide insulation to the side ears of the clips. In addition to...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 6

Product Specifications and Selection Guide Overcurrent Protection Technologies FUSE PRODUCTS Fuses provide protection by completely stopping the flow of energy to sensitive circuits. If current exceeds the fuse’s operating range, the metal wire or strip melts safely within an enclosure. Littelfuse offers the most extensive range of fuses available, and for easy replacement of cartridge fuses Littelfuse offers a wide selection of fuseholders including panel mount, in-line, and surface and thru-hole circuit board mount devices. See page 6 for fuseholder selection. RoHS Compliant Lead Free...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 7

Lead Free RoHS Compliant Agency Approvals 3 Operating Temperature Range Interrupting Rating at Max Voltage Rating 3 (Amps) Max. Voltage Rating 3 (Volts) Very Fast Acting Fast Acting Medium Acting Order Samples View Datasheet Device Range 3 (Operating Current Options in Amps) Radial Leaded / Socket: Micro Fuse / TR3 Fuse ™ Axial Leaded / Cartridge: PICO® Fuse / PICO® II Fuse Axial • • • • • • • • • • • • • • Special Fuse • • • • • • • • • • • • • • • • • • • • • • • • • 1000VAC / DC High Voltage Fuse

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Littelfuse Electronics Circuit Protection Product Selection Guide - 8

Overcurrent Protection Technologies (continued) FuseHolder Selection Guide Wire Wire Connector Terminals Fuseholder Type Panel Mount Fuse Enclosures TH= Thru-Hole SM= Surface Mount CT= Wire Connector Terminal QC= Quick Connect Circuit Board Mount Fuse Enclosures Fuse Blocks Fuse Clips Fuse Series Fuse Type Circuit Connection Method 870 Series Medical Grade 820/ 820-20 Series Mini Shocksafe 348 Series Snap Mount 340 Series RF Shielded / Watertight

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Littelfuse Electronics Circuit Protection Product Selection Guide - 9

Agency Approvals Lead Free Max Fault current (IMAX) Halogen Free Hold Current (IHOLD) Order Samples View Datasheet PTCs (positive temperature coefficient) increase resistance as temperature increases. They are designed to prevent unsafe levels of current while allowing constant safe current levels, and their resistance will “reset” automatically when the current and temperature returns to a safe level. PTCs are typically used in applications where automatic reset is desired. Operating Temperature Range Surface Mount: LoRho PTC (Low Resistance) Radial Leaded: Battery Strap: SL (Low...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 10

Overvoltage Suppression Protection Varistor Products Halogen Free Operating Lines Mount/ Temperature Protected Form Factor Range Technology Type Operating Peak Current Peak Energy DC Voltage Range (J) Range2 (A) Range Lead Free Agency Approvals Operating AC Voltage Range Order Samples View Datasheet Shorthand for “Variable Resistors,” Varistors possess characteristics that divert transient currents away from sensitive components. Littelfuse offers two types: Miniature surface mount Multi-Layer Varistors (MLVs) for small electronics applications and Metal Oxide Varistors (MOV) for higher...

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Littelfuse Electronics Circuit Protection Product Selection Guide - 11

GDT Products GDTs (gas discharge tube) dissipate voltage transients through a contained plasma gas. They have high insulation resistance plus low capacitance and leakage to ensure minimal effect on normal operation of equipment. Littelfuse devices offer a small footprint and are available in leaded and surface mount configurations, with high surge handling capability. Their fast response to transient over-voltage events, and ability to dissipate large amounts of energy, translates into reduced risk of equipment damage. The amount of energy they can dissipate makes them a good choice for...

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